Special Offer: SAVE 600nok per person. Book a combination aurora borealis chase and scenic day tour during the months of September, October or November 2019 for the special price of 1800 kr. Check Marianne's webpage for details!

NEW COSMIC RAY DATA FEED ON SPACEWEATHER.COM: As Solar Minimum deepens, cosmic rays are intensifying. You can now watch the daily change in radiation right here on Spaceweather.com. A new data feed displays neutron monitor measurements from the University of Oulu's Cosmic Ray Station in Finland. Radiation levels are now just percentage points away from setting a Space Age record: full story.

IRISH SKIES TURN PURPLE: Decaying hurricane Lambert swept past Ireland yesterday. Curiously, when the skies cleared they weren't blue. "They were purple," reports John Murphy, who sends this picture from Cork City:

"As Oct. 3rd came to an end, strong gusts and heavy rain eventually gave way to this volcanic sunset," he says.

That's right. Hurricane Lambert didn't cause the strangely colored sunset. The Raikoke volcano did. Located in Russia's Kuril islands, Raikoke erupted on June 22nd, pushing volcanic aerosols high into the stratosphere. They're still up there. Apparently, one of the sulfurous plumes followed Hurricane Lambert across Ireland Oct 3rd, painting the sunset sky with unusual color.

Why purple? Fine volcanic aerosols in the stratosphere scatter blue light which, when mixed with ordinary sunset red, produces a purple hue. Months after Raikoke erupted, sky watchers around the world are still seeing purple skies when its emissions float by. Browse the gallery for more examples.

Realtime Volcanic Sunset Photo Gallery
Free: Spaceweather.com Newsletter

A MULTIPLE ANALEMMA: If you took a picture of the sun at the same time each day, would it remain in the same position? The answer is no, and the figure-8 shape traced out by the sun over the course of a year is called an analemma. Over the years, Spaceweather.com has featured many beautiful analemmas ... but none like this. John Dartnell of North Wiltshire, UK, photographed the sun 24 times a day for a whole year, creating a rare multiple "biscuit tin" analemma:

"I made a pinhole camera from a biscuit tin," explains Dartnell. "Exposures were controlled by a battery driven clock. A rotating disc with a cut out slot acted as a shutter to give an exposure every hour. The resulting image shows six analemmas with traces of three others."

In all, this one picture captures 12 months of exposure time on a single photographic paper--from Sept. 2018 to Sept.  2019. The upper and lower tips of each "8" represent the solstices--the longest and shortest days of the year. Equinoxes occur near the necks.

"Making an analemma in the UK is a challenge because of our cloudy weather," says Dartnell. "You can't consistently see the sun at noon.  That why I decided on this approach of setting up a pinhole camera that could record the sun at intervals throughout the day. As you can imagine, at the end of the year I opened up the tin with a mixture of great anticipation and potential disappointment. I was glad to see it was a success."

Realtime Analemma Photo Gallery
Free: Spaceweather.com Newsletter

THE ANTARES PENDANT: Are you looking for a far-out gift? Consider the Antares Pendant. On Aug. 19, 2019, the students of Earth to Sky Calculus launched a cosmic ray balloon to the edge of space, 104,002 ft high. This ruby-red crystal necklace went along for the ride:

You can have it for $179.95. The students are selling these white gold-plated pendants to support their cosmic ray ballooning program. The glittering Swarovski crystal has a deep ruby hue inspired by the red-supergiant star Antares in Scorpio. Each one comes with greeting card showing the pendant in flight and telling the story of its journey to the edge of space and back again.

Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education

Realtime Space Weather Photo Gallery
Free: Spaceweather.com Newsletter

Realtime Aurora Photo Gallery
Free: Spaceweather.com Newsletter

On Oct. 3, 2019, the network reported 22 fireballs.
(21 sporadics, 1 southern Taurid)

In this diagram of the inner solar system, all of the fireball orbits intersect at a single point--Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). [Larger image] [movies]

Recent & Upcoming Earth-asteroid encounters:

Asteroid	Date(UT)	Miss Distance	Velocity (km/s)	Diameter (m)
2019 TA	2019-Sep-29	1.2 LD	6.2	5
2019 SE5	2019-Sep-29	5.7 LD	6.6	15
2019 SO1	2019-Sep-29	11.3 LD	7.5	16
2019 SA5	2019-Sep-29	19.2 LD	7.8	25
2019 TD	2019-Sep-29	0.3 LD	10.1	5
2019 TF	2019-Sep-29	18 LD	10	11
2019 SN4	2019-Sep-29	6.5 LD	19.6	48
2019 TC	2019-Sep-29	14.5 LD	12.3	19
2019 SH3	2019-Sep-30	3.1 LD	14.2	27
2019 SN3	2019-Sep-30	2.2 LD	7.7	16
2019 SP	2019-Sep-30	6.6 LD	15.1	46
2019 TR	2019-Oct-01	15.7 LD	8.1	28
2019 SJ9	2019-Oct-01	7.8 LD	8.4	14
2019 SM8	2019-Oct-01	0.4 LD	14.2	5
2019 SE8	2019-Oct-01	2.8 LD	22.8	15
2019 SE9	2019-Oct-01	14.1 LD	4.1	37
2018 FK5	2019-Oct-01	13.3 LD	10.5	8
2019 SD8	2019-Oct-02	1.4 LD	10.9	12
2019 SX3	2019-Oct-02	8.7 LD	8.7	30
2019 SA6	2019-Oct-02	11.8 LD	16.6	30
2019 TW	2019-Oct-02	4.5 LD	3.7	10
2018 LG4	2019-Oct-02	13.8 LD	8.1	12
2019 SL8	2019-Oct-03	7.9 LD	13.3	24
2019 SP3	2019-Oct-03	1 LD	8.7	20
2019 SH9	2019-Oct-03	4.6 LD	14.9	10
2019 TK	2019-Oct-03	1.2 LD	13.9	9
2019 TX	2019-Oct-04	1.3 LD	7.3	7
2019 TV	2019-Oct-05	4.1 LD	9.1	9
2017 TJ4	2019-Oct-05	13.5 LD	8.9	32
2019 SZ4	2019-Oct-06	18.7 LD	6.5	25
2019 TH	2019-Oct-06	14.7 LD	11.5	26
2019 TU	2019-Oct-08	4.4 LD	9.8	21
2019 RK	2019-Oct-08	16.7 LD	3	30
2019 TC1	2019-Oct-08	3.5 LD	13.1	12
2019 SB6	2019-Oct-08	7.8 LD	7.8	16
2019 TM	2019-Oct-08	9.4 LD	12.9	38
2019 TS	2019-Oct-08	8.4 LD	7.8	29
2019 TZ	2019-Oct-09	8 LD	11.6	16
2019 SL7	2019-Oct-09	1.4 LD	17.1	22
2019 SX5	2019-Oct-10	17.7 LD	21.8	82
2019 SK8	2019-Oct-12	10.5 LD	8.4	21
2019 SV9	2019-Oct-12	8.6 LD	13.6	30
2019 SE2	2019-Oct-12	19.2 LD	10.2	54
2019 SR8	2019-Oct-16	13.5 LD	9.8	26
2019 TA1	2019-Oct-18	15.2 LD	6.5	22
2019 SJ8	2019-Oct-19	11.6 LD	7.4	47
162082	2019-Oct-25	16.2 LD	11.2	589
2017 TG5	2019-Oct-25	14.4 LD	11.9	34
2015 JD1	2019-Nov-03	12.9 LD	11.9	269
2010 JG	2019-Nov-12	19.6 LD	14.9	235
481394	2019-Nov-21	11.3 LD	7.9	372
2008 EA9	2019-Nov-23	10.5 LD	2.2	10

Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach.

Cosmic Rays in the Atmosphere

SOMETHING NEW! We have developed a new predictive model of aviation radiation. It's called E-RAD--short for Empirical RADiation model. We are constantly flying radiation sensors onboard airplanes over the US and and around the world, so far collecting more than 22,000 gps-tagged radiation measurements. Using this unique dataset, we can predict the dosage on any flight over the USA with an error no worse than 15%.

E-RAD lets us do something new: Every day we monitor approximately 1400 flights criss-crossing the 10 busiest routes in the continental USA. Typically, this includes more than 80,000 passengers per day. E-RAD calculates the radiation exposure for every single flight.

The Hot Flights Table is a daily summary of these calculations. It shows the 5 charter flights with the highest dose rates; the 5 commercial flights with the highest dose rates; 5 commercial flights with near-average dose rates; and the 5 commercial flights with the lowest dose rates. Passengers typically experience dose rates that are 20 to 70 times higher than natural radiation at sea level.

To measure radiation on airplanes, we use the same sensors we fly to the stratosphere onboard Earth to Sky Calculus cosmic ray balloons: neutron bubble chambers and X-ray/gamma-ray Geiger tubes sensitive to energies between 10 keV and 20 MeV. These energies span the range of medical X-ray machines and airport security scanners.

Column definitions: (1) The flight number; (2) The maximum dose rate during the flight, expressed in units of natural radiation at sea level; (3) The maximum altitude of the plane in feet above sea level; (4) Departure city; (5) Arrival city; (6) Duration of the flight.

SPACE WEATHER BALLOON DATA: Approximately once a week, Spaceweather.com and the students of Earth to Sky Calculus fly space weather balloons to the stratosphere over California. These balloons are equipped with radiation sensors that detect cosmic rays, a surprisingly "down to Earth" form of space weather. Cosmic rays can seed clouds, trigger lightning, and penetrate commercial airplanes. Furthermore, there are studies ( #1, #2, #3, #4) linking cosmic rays with cardiac arrhythmias and sudden cardiac death in the general population. Our latest measurements show that cosmic rays are intensifying, with an increase of more than 18% since 2015:

The data points in the graph above correspond to the peak of the Reneger-Pfotzer maximum, which lies about 67,000 feet above central California. When cosmic rays crash into Earth's atmosphere, they produce a spray of secondary particles that is most intense at the entrance to the stratosphere. Physicists Eric Reneger and Georg Pfotzer discovered the maximum using balloons in the 1930s and it is what we are measuring today.

En route to the stratosphere, our sensors also pass through aviation altitudes:

In this plot, dose rates are expessed as multiples of sea level. For instance, we see that boarding a plane that flies at 25,000 feet exposes passengers to dose rates ~10x higher than sea level. At 40,000 feet, the multiplier is closer to 50x.

The radiation sensors onboard our helium balloons detect X-rays and gamma-rays in the energy range 10 keV to 20 MeV. These energies span the range of medical X-ray machines and airport security scanners.

Why are cosmic rays intensifying? The main reason is the sun. Solar storm clouds such as coronal mass ejections (CMEs) sweep aside cosmic rays when they pass by Earth. During Solar Maximum, CMEs are abundant and cosmic rays are held at bay. Now, however, the solar cycle is swinging toward Solar Minimum, allowing cosmic rays to return. Another reason could be the weakening of Earth's magnetic field, which helps protect us from deep-space radiation.

Essential web links

NOAA Space Weather Prediction Center

The official U.S. government space weather bureau

Atmospheric Optics

The first place to look for information about sundogs, pillars, rainbows and related phenomena.

Solar Dynamics Observatory

Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever.

STEREO

3D views of the sun from NASA's Solar and Terrestrial Relations Observatory

Solar and Heliospheric Observatory

Realtime and archival images of the Sun from SOHO.

Daily Sunspot Summaries

from the NOAA Space Environment Center

NOAA 27-Day Space Weather Forecasts

fun to read, but should be taken with a grain of salt! Forecasts looking ahead more than a few days are often wrong.

Aurora 30 min forecast

from the NOAA Space Environment Center

Heliophysics

the underlying science of space weather

Spaceweather.com welcomes these supporters of science communication: RV Sales and CRAS, the Conservatory of Recording Arts and Sciences and Windshield Replacement Phoenix and Breast Augmentation Phoenix and Dentist Chandler, AZ.

Look no further to find the best Comox Valley Real Estate listings and homes for sale

NASA Near Earth Asteroid Home Page

Chicago SEO Expert

Search Kelowna Real Estate Listings & Homes for Sale easily. Find help on all Calgary Homes For Sale and Real Estate Listings. Great source for Edmonton Real Estate Listings & Homes For Sale

The best place for soundcloud followers buy is definitely BRSM.IO

To find reviews of new online casino sites in the UK try The Casino DB where there are hundreds of online casino reviews complete with bonuses and ratings. Looking for a new online casino? Try Casimpo the new site dedicated to making online casino simple and easy for all.

These links help Spaceweather.com stay online. Thank you to our supporters!

more links...